People often choose dogs that they believe reflect aspects of their own personalities. This man looked so much like his dog that he won $2,620 in a contest.

Image courtesy © Koji Sasahara / Associated Press

Other Criteria for Attraction

Finding out what attracts one person to another has been explored by matchmakers and psychologists alike. But science has been able to go beyond many of the classic answers, such as sense of humor, kindness, intelligence and similar values. The genetic basis of attraction may be equally important while also representing a bigger mystery.

A study involving researchers from several universities showed that women prefer men who look like their fathers. Even women who were adopted seem to share the same predilection. Tamas Bereczkei, a researcher at Hungary's University of Pecs who was involved in the study, called the process sexual imprinting. Women use their fathers as models by which they judge their prospective mates.

The study also found that a close father-daughter relationship more often resulted in a woman marrying someone who looked like her father. Again, the notion of imprinting arises as these fathers, by forming close emotional bonds with their daughters, seemed to provide a model of what a husband should be.

Other studies have shown that the waist-to-hip ratio provides a subtle but important cue in determining attractiveness. Men prefer women with a waist-to-hip ratio of 0.7, which means that a woman's body appears capable of producing healthy children. Women often prefer men with a waist-to-hip ratio of 0.8 to 1.0, though other features like height or a broad chest are also important. Not by coincidence, waist-to-hip ratio has a genetic basis. Our hormones determine where the body accumulates fat, and a desirable waist-to-hip ratio would indicate a proper hormonal balance, and consequently, a healthy mate.

Symmetrical facial features are considered to be another desirable trait. Implicitly, symmetry is a sign of good development and the ability to produce healthy children. In past studies, test subjects rated more symmetrical men and women as healthier and more attractive. Dr. Randy Thornhill, an evolutionary biologist at the University of New Mexico, found that men who are more symmetrical have more sexual partners than their less-symmetrical peers. One reason, Thornhill says, is that women are frequently the objects of competition, so they're able to be more selective [Source: Live Science].

In the end, it appears that genetics and shared experiences are very important, not only in the partners we choose but also in how we grow old together. We generally want someone who's like us and like the role models we know, but we also want, as the saying goes, someone with whom we can grow old and who will change and adapt with us in the years to come. It just so happens that, when that experience works out, we can end up looking like the person we love.

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